"KDE has released a first beta of the upcoming 4.7 release of the Plasma Desktop and Netbook workspaces, the KDE Applications and the KDE Frameworks, which is planned for July 27, 2011. With API, dependency and feature freezes in place, the KDE team's focus is now on fixing bugs and further polishing new and old functionality."

This obviously begs two questions: are there really many mobile devices which can even run full KDE experience yet only provides OpenGL ES

The OpenGL ES support is primarily for Plasma Active which is exactly not a "full KDE experience". Furthermore OpenGL ES is also a requirment for Wayland, so ES support was not primarily added only for mobile devices.

and would it be possible to support both OpenGL ES for mobiles for compatibility AND the full-blown OpenGL spec for more capable devices for better performance?

Well that's what we are doing. The desktop system uses OpenGL and OpenGL ES needs to be enabled as a compile time option. But don't expect that OpenGL gives you a better performance than OpenGL ES, I would say the opposite is true.

Btw. it doesn't make much sense to raise requirements to OpenGL 3 or 4. They hardly provide anything we need and that can be used with OpenGL 2 plus the additional extensionsion.